'You Know Who I Am, Right?'

Uh, yeah, you're apparently a crackhead.

Allegedly, of course.

Troubled Oscar-winning actress Tatum O'Neal, who has spoken and written about her years-long battle with addiction, was busted last night just blocks from her Lower East Side luxury apartment - charged with buying cocaine and crack, sources said.

The 44-year-old actress - who became the youngest-ever to snag an Oscar, at age 10, for her role in "Paper Moon" - was arrested at 7:30 p.m. by detectives from Manhattan South Narcotics on Clinton Street between East Broadway and Grand Street, the sources said.

"When the police approached, she asked them, 'You know who I am, right?'" one source told The Post.

"Then she said, 'I'm researching a part - I'm doing this for a part' " as a junkie.

The source said detectives found a pipe on O'Neal, daughter of actor Ryan O'Neal. The pipe and screen were clean.